Alcohol

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ALCOHOL

SUBJECT : ALTERNATE FUELS & ENERGY
M.E. (I.C. ENGINE & AUTOMOBILE) 1 st SEM.
L.D.C.E. AHMEDABAD

PREPARED BY : VIVEK
DHAMELIYA
HARDIK BAMBHANIA

 
1. INTRODUCTION

There is nothing new in the use of
alcohol as a fuel. In 1872, when
Nikolaus Otto invented the internal
combustion engine, gasoline was not
available. Ethyl alcohol was the
specified fuel. The model “T” Ford
was designed to run on the available
crude gasoline, alcohol, or any
combination of two.



2. CLASSIFICATION
Generally

two types of alcohol are
used as a fuel, Methanol and
Ethanol. Methanol (CH3OH) is an
alcohol with one carbon, Ethanol
(CH3CH2OH) is an alcohol with two
carbons.

A) METHANOL

Methanol,

also known as methyl
alcohol, wood alcohol, wood
naphtha or wood spirits, is a
 chemical  with the formula CH3OH

Methanol

acquired the name "wood
alcohol" because it was once
produced chiefly as a byproduct of
the destructive distillation of wood.

• Production

i) From synthesis gas
 Carbon monoxide and hydrogen
react over a catalyst to produce
methanol.
CO + 2 H2 → CH3OH
Today,

the most widely used
catalyst is a mixture of copper, zinc
oxide, and alumina

ii) From methane
A direct catalytic conversion of
methane to methanol using Cuzeolites or other catalysts is an
alternative process for the efficient
production
of
methanol.



• Properties
 
1.

2.

3.
4.
5.

It has very high latent heat of
vaporization (volatility) (474 Btu/lb)
which is around three time higher than
the volatility of gasoline (140 Btu/lb)
Combustion of Methanol required less
stoichiometric air ratio (6.45 : 1)
whereas in case of gasoline combustion
it is 15 : 1.
Boiling temperature 1450 F ( 620 C)
It has high octane number (106)
It is a light, colorless and toxic in nature

• Advantages
1.

2.

3.
4.
5.

Due to high latent of vaporization methanol
and air mixture cool down three times more
than gasoline air mixture which increase the
volumetric mass efficiency and hence power
output.
Due to very high octane number it has good
antiknock characteristic and it can allow the
use of high compression ratio.
Only slight change is required for conversion
of gasoline system to methanol system.
Water injection is possible to increase the
power.
It has very less sulphur content.

• Disadvantage
1.
2.

3.
4.
5.

Calorific value is low compared to
gasoline so reach fuel mixture is required.
It is more corrosive than gasoline so
special oil additives are necessary in
order to protect the engine.
It is a toxic in nature.
Methanol flame is colorless so present of
fire cannot be easily detected.
Methanol, being a pure chemical
compound, has a single boiling point, so
that it can cause cold-start problems in
cold weather or vapor lock in hot.

B) ETHANOL

Commonly referred to simply as
alcohol or spirits, ethanol is also
called ethyl alcohol, it is used as
a solvent, as an antiseptic, as
a fuel and as the active fluid in
modern (postmercury) thermometers. It is
a volatile, flammable, colorless
liquid with the structural
formula CH3CH2OH, often
abbreviated as C H OH or C H O.



• Production
i) Fermentation
Ethanol is produced by microbial
fermentation of the sugar(From
sugar cane) and starch( From corn).
Microbial fermentation currently
only works directly with sugars.
C12H22O11 + H2O → 4 CH3CH2OH + 4
CO2
C6H12O6→ 2 CH3CH2OH + 2 CO2

ii) Ethylene hydration
 Ethanol

for use as an industrial
feedstock or solvent is made
from petrochemical feed stocks,
primarily by the acidcatalyzed hydration of ethylene,
represented by the chemical equation.
C2H4 + H2O → CH3CH2OH

The

catalyst is most
commonly phosphoric acid

• Properties
1.

2.

3.
4.

It has very high latent heat of
vaporization (volatility) (361 Btu/lb)
which is around 2.5 time higher than
the volatility of gasoline (140 Btu/lb)
Combustion of ethanol required less
stoichiometric air ratio (9 : 1) whereas
in case of gasoline combustion it is 15 :
1.
Boiling temperature 173.3 0 F (78.5 0
C)
It has high octane number (106).

• Advantages
1.
2.
3.

4.

Regular cars can handle up to 10%
ethanol without engine reconstruction.
Unlike gasoline, ethanol is renewable
resource.
Ethanol burns more cleanly in air than
petroleum, producing less carbon
(soot) and carbon monoxide.
Due to very high octane number it has
good antiknock characteristic and it
can allow the use of high compression
ratio.

• Disadvantages
1.
2.

3.
4.

5.

Ethanol has lower calorific value.
Large amount of land are required
to produce crops to obtain
ethanol.
It is corrosive in nature.
Typical current engine require
modification to use high
concentration of ethanol.
There is a danger of storage tank
due to lower vapor pressure.

4. METHODS OF UTILISATION
A) Alcohol blends
Alcohol

blends have the advantage
that up to 10 % concentration of
alcohol may be used without
modification to the engine.
The main disadvantage is that the
alcohol you use must be perfect
dry. However drying the alcohol
does require a separate

B) Pure alcohol
The advantages of burning
relatively pure 80 to 95% alcohol
are several. First of all, because the
drying step is unnecessary overall
cost is less than the gasoline.
Secondly, you can leave 5 to 15%
water in the alcohol and you get
advantage of water injection.
The only disadvantage is the


C) Diesel engine
Generally

diesel engine can be run
on pure alcohol, but the main
problem is in the lubrication of the
injectors. This is solved by the
addition of 5 to 20% vegetable oil
to the alcohol.

QUESTIONS
Explain the advantages and
disadvantages of using Methanol
in I.C. engine.
2. Explain the advantages and
disadvantages of using Ethanol in
I.C. engine.
3. Explain the production process for
Methanol and Ethanol.
4. What are the methods for
utilization of alcohol in I.C.
1.

THANK YOU

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